In some situations, it is desirable for a hearing system that includes first and second hearing devices to render (e.g., acoustically present) streaming audio from an audio source (e.g., a Bluetooth-enabled smartphone) to a user. To this end, the first hearing device may establish a wireless link (e.g., a Bluetooth link) with the audio source and receive audio packets transmitted from the audio source over the wireless link in accordance with an acknowledgement-based transmission protocol. The acknowledgement-based transmission protocol requires the first hearing device to acknowledge successful receipt of an audio packet transmitted by the audio source before the audio source transmits a subsequent audio packet.
For various reasons (e.g., technical limitations, power consumption constraints, etc.), it may be impossible or undesirable for the second hearing device to establish and maintain its own wireless link with the audio source while a wireless link is maintained between the first hearing device and the audio source. In these situations, to facilitate rendering of the streaming audio by the second hearing device, the first hearing device may transmit eavesdropping instructions to the second hearing device by way of a wireless support link that interconnects the hearing devices. The eavesdropping instructions allow the second hearing device to eavesdrop on the wireless link established between the first hearing device and the audio source to receive the audio packets while the audio packets are being transmitted by the audio source over the wireless link. The second hearing device may store the audio packets in a buffer as the audio packets are received and render the audio by playing back the audio packets from the buffer.
At some point, it may be desirable for both the first and second hearing devices to stop rendering the streaming audio. In conventional configurations, this is accomplished by the first hearing device transmitting a stop command to the second hearing device by way of the wireless support link. Upon receipt of the stop command, the second hearing device stops playing back the audio packets from the buffer.
Unfortunately, the wireless support link typically has relatively little bandwidth and relatively high latency. This may delay the second hearing device from receiving and executing the stop command by hundreds of milliseconds (e.g., 300 milliseconds (“ms”) or more). This may cause the first and second hearing devices to stop rendering the streaming audio at noticeably different times, which is annoying and undesirable from the user's perspective. Moreover, the wireless support link may become disabled, thereby isolating the second hearing device from the first hearing device. This may make it impossible for the first hearing device to transmit the stop command to the second hearing device.